https://pastebin.com/dKmsDmGV this is the pastebin link for the log as it does not generate a crash

You do have Sponge mixins, they're bundled as part of VanillaFix.

While I haven't been able to reproduce your exact crash, the new Farseek 2.3.2 has several compatibility improvements with SpongeForge so please give it a try and let me know if it resolves the issue for you.